1. Field of the Invention
The invention relates to an apparatus for ventilation of a casting mold.
2. Description of the Related Art
When filling a casting mold, for example during high-pressure or low-pressure casting, during chill casting or some other casting method, the air situated in the casting mold has to be removed from the casting mold in order to achieve a clean casting result without cavities and porosities. This can either be done actively, by means of evacuation of the mold before the actual filling process, passively by means of displacement of the air during introduction of the casting material, or by means of a combination of these two methods.
Apparatuses for ventilation of a casting mold in the form of what are called chill vents are known from DE 202 08 464 U1 or DE 20 2010 006 751 U1. With these valve devices, ventilation of the mold takes place by means of a washboard-shaped, labyrinth-shaped or meander-shaped gap in a block-like valve body made from a highly conductive material, whereby after removal of the air from the casting mold, casting material from the casting mold enters into the gap in the valve body and solidifies there. In this way, it is ensured that all the air is removed from the mold and a satisfactory casting result is achieved.
Because of the high flow velocity of the casting material in the valve body, increased wear of the valve body occurs in the inflow region. It is known to configure the valve body with wear-resistant material in the inflow region, but such wear-resistant materials are relatively expensive.